Kriemhild is the sister of king Gunnar, she falls in love with Sigurd, who does not care for her, as he is in love with the valkyrie Brynhild, to whom he once gave the ring of Andvaranaut. Gudrun's brother Gunnar also wished to marry Brynhild, but this was impossible as she had sworn to marry only the man who could defeat her in a fair fight, whom she knew to be Sigurd.
Later, when Brynhild learns that she has been tricked into marrying the inferior Gunnar, she exacts vengeance by telling Gunnar that Sigurd had taken liberties with her, so Gunnar has Sigurd killed. Gudrun is so overcome with grief at the death of the one she loves that she cannot weep, the royal court fears for her life, and when finally her sister shows Sigurd's corpse to Gudrun, tears flow at last. Gudrun laments her lost husband and predicts the death of his killer, her own brother Gunnar.
Gudrun later marries king Atli (loosely based on Attila the Hun); in the northern version, Atli is responsible for the death of her whole family, who bear the name Völsung/Niebelungen after the Nibelung gold treasure. The queen takes revenge for her murdered family by killing her two sons by Atli and serving them to their father at a feast. Then, when Atli is solidly drunk, she breaks the news to him:
Thou giver of swords, of thy sons the hearts
All heavy with blood in honey thou hast eaten;
Thou shalt stomach, thou hero, the flesh of the slain,
To eat at thy feast, and to send to thy followers.
Thou shalt never call to thy knees again
Erp or Eitil, when merry with ale;
Thou shalt never see in their seats again
The sharers of gold their lances shaping,
(Clipping the manes / or minding their steeds.)
Gudrun sets fire to Atli's hall, killing him along with all of his men, she tries to drown herself by jumping into the sea with an armful of stones. The waves find her revenge fitting, however, and instead of drowning her, they carry her to Sweden, where she marries another king, Jónakr, with whom she has three sons Hamdir, Sörli and Erp. Svanhild, her daughter by Sigurd, is wooed by Ermanaric, but is accused wrongly of adultery and is killed by her husband. Gudrun also has a son by Sigurd, named Sigmund (named after Sigurd's father). Subsequently, her three sons are killed when they avenge Svanhild
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